From 583fee3e12df0e6f1f66f063b989d8e7fed0e65a Mon Sep 17 00:00:00 2001
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Date: Sun, 6 Oct 2019 17:57:54 -0700
Subject: [PATCH] fs: ocfs2: fix a possible null-pointer dereference in
ocfs2_write_end_nolock()
Git-commit: 583fee3e12df0e6f1f66f063b989d8e7fed0e65a
Patch-mainline: v5.4-rc3
References: git-fixes
In ocfs2_write_end_nolock(), there are an if statement on lines 1976,
2047 and 2058, to check whether handle is NULL:
if (handle)
When handle is NULL, it is used on line 2045:
ocfs2_update_inode_fsync_trans(handle, inode, 1);
oi->i_sync_tid = handle->h_transaction->t_tid;
Thus, a possible null-pointer dereference may occur.
To fix this bug, handle is checked before calling
ocfs2_update_inode_fsync_trans().
This bug is found by a static analysis tool STCheck written by us.
Link: http://lkml.kernel.org/r/20190726033705.32307-1-baijiaju1990@gmail.com
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>
---
fs/ocfs2/aops.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 50d56d9a0475..9cd0a6815933 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -2049,7 +2049,8 @@ int ocfs2_write_end_nolock(struct address_space *mapping,
inode->i_mtime = inode->i_ctime = current_time(inode);
di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
- ocfs2_update_inode_fsync_trans(handle, inode, 1);
+ if (handle)
+ ocfs2_update_inode_fsync_trans(handle, inode, 1);
}
if (handle)
ocfs2_journal_dirty(handle, wc->w_di_bh);
--
2.35.3